Such behaviour could be start of serious issue? (8)

I believe the answer is:

sedition

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'such behaviour' is the definition.
'sedition' can be an answer for 'behaviour' (I have seen 'Revolting behaviour' mean 'sedition' so perhaps 'behaviour' could also mean 'sedition'). I am not sure about the 'such' bit.

'start of serious issue?' is the wordplay.
'start of' says to take the initial letters.
'issue?' becomes 'edition' (edition is a kind of issue).
The first letter of 'serious' is 's'.
's'+'edition'='SEDITION'

'could be' is the link.

Can you help me to learn more?

(Other definitions for sedition that I've seen before include "Incitement to riot" , "Subversive activity" , "agitation" , "revolt" , "Stirring up of rebellion or disorder" .)

I've seen this clue in The Times.

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